1. Field of the Invention
The present invention relates to a light source module using quantum dots, a backlight unit employing the light source module, a display apparatus, and an illumination apparatus.
2. Description of the Related Art
Quantum dots are nano crystals having diameters equal to or less than about 10 nm, are formed of a semiconductor material, and cause a quantum confinement effect. Quantum dots generate more intensive light in a narrower wavelength band in comparison to typical phosphor. Quantum dots emit light while excited electrons transit from a conduction band to a valence band, and have characteristics that a wavelength of light varies according to particle sizes even in the same material. Since the wavelength of light varies according to a size of the quantum dots, light having a desired wavelength region may be obtained by controlling the size of the quantum dots.
Quantum dots are naturally coordinated and dispersed in an organic solvent. If quantum dots are not appropriately dispersed or are exposed to oxygen or moisture, light emission efficiency is reduced. In order to solve this problem, a method of capping quantum dots with an organic material or a material having a large band gap has been developed. However, a problem of the above method has been pointed out with respect to utility in view of a process or a cost. Accordingly, a method of utilizing quantum dots more stably with a higher light emission performance is required. For example, a method of protecting quantum dots from oxygen or moisture by inserting an organic solvent or a polymer, in which the quantum dots are dispersed, into a polymer cell or a glass cell is suggested and attempted to be used in an illumination apparatus.